Information providing method for vehicle and information providing device for vehicle

ABSTRACT

In an information providing method and device for a vehicle, an engine of the vehicle is stopped automatically when a predetermined permission condition is satisfied in a state in which the vehicle is stopped by a brake operation executed by a driver. The driver is notified of support information for satisfying the permission condition when the permission condition is not satisfied in the state in which the vehicle is stopped by the brake operation. A vehicle stop keeping control generates a braking force capable of maintaining a vehicle stopped state even when the brake operation decreases. The notification of the support information is stopped when it is determined that the driver does not wish to automatically stop the engine in a state in which the support information is being notified and the vehicle stop keeping control is in operation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. national stage application of InternationalApplication No. PCT/JP2015/005470, filed on Oct. 30, 2015.

BACKGROUND

Field of the Invention

The present invention relates to an information providing method for avehicle and an information providing device for a vehicle.

Background Information

Conventionally, in an idle stop technique (also referred to as an idlereduction, idling stop) that automatically stops an engine, a techniqueis known for informing or notifying the driver of a control state, forexample, as described in Japanese Laid-open Patent Application No.2014-159752 A, hereinafter “Patent Document 1.” According to thetechnique described in Patent Document 1, in an idle stop unactuatedstate or the out-of-operation of the idle stop, information forprompting an idle stop to encourage the driver to stop the engine (inthe description below, referred to as “support information”) will bedisplayed by an indicator light and the like to inform a driver. Notethat the out-of-operation of the idle stop is caused by a state in whichan operation amount of a brake pedal by the driver is less than apredetermined value, for example. Further, the support informationindicates information and the like such that the operation amount of thebrake pedal will be encouraged or urged to reach a predetermined valueor more.

SUMMARY

However, in the technique described above in Patent Document 1, aproblem likely to occur is that the support information will becontinuously broadcast even when the driver does not want the operationof the idle stop in situations that the operation amount of the brakepedal is kept less than the predetermined value. The present inventionhas been made in view of the above problem and aims to provide aninformation providing method for a vehicle and an information providingdevice for a vehicle in which the notification of the supportinformation is able to be stopped in situations where the driver doesnot want the operation of the idle stop.

In order to solve the above problem, according to one aspect of thepresent invention, the engine will be caused to be stopped automaticallywhen a predetermined permission condition is satisfied in a state inwhich the vehicle is stopped with a brake operation by the driver.Further, when the permission condition is not satisfied or establishedin the state in which the vehicle is stopped by the brake operation,support information for satisfying the permission condition is notifiedto the driver. Furthermore, in a state in which the support informationis being notified and a vehicle stop keeping control for generating abraking force capable of maintaining the vehicle in a stopped state evenif the brake operation is reduced is activated, then the notification ofthe support information will be stopped upon determining that the driverdoes not wish to stop the engine automatically.

According to one aspect of the present invention, in a state in whichthe support information is notified and the vehicle stop keeping controlis in operation, the notification of the support information is stoppedwhen determined that the driver does not wish to automatically stop theengine. Thus, it is possible to provide an information providing methodand an information providing device for a vehicle that can stop thenotification of the support information in a situation where the driverdoes not want the operation of the idle stop.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a configuration of a vehicleinformation providing device of a first embodiment according to thepresent invention;

FIG. 2 is a diagram showing a state in which support information isturned on or lit on a display device;

FIG. 3 is a flow chart showing processing of the vehicle informationproviding device that implements the first embodiment according to thepresent invention;

FIG. 4 is a time chart showing an operation of the vehicle to which aconfiguration of the vehicle information providing device in the firstembodiment is applied according to the present invention; and

FIG. 5 is a diagram illustrating a modification of the first embodimentaccording the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the following detailed description, a description will be given ofspecific details of embodiments according to the present invention so asto provide a thorough understanding. However, even without such specificdetails, it is clear that one or more embodiments may be implemented.Further, in order to be concise with the drawings, well-known structuresand devices may be shown only schematically.

First Embodiment

Below, a description will be given of a first embodiment according tothe present invention with reference to the drawings.

Configuration of Information Providing Device For Vehicle

With reference to FIGS. 1 and 2, the configuration of the vehicleinformation providing device 1 in the first embodiment is described. Asrepresented in FIG. 1, the information providing device for a vehicle 1includes an idle stop control unit 10 and an information notificationunit 20. The idle stop control unit 10 is configured, for example, by amicrocomputer, and is mounted on a vehicle equipped with a vehicleinformation providing device 1 (in the description below, referred to as“vehicle”). Incidentally, the microcomputer is configured with, forexample, a CPU (Central Processing Unit), a RAM (Random Access Memory),and a ROM (Read Only Memory). Further, the idle stop control unit 10receives input of information signals of a mode selection switch 2, avehicle speed calculating unit 4, a brake sensor BPS, and a hydraulicpressure sensor 6.

The mode selection switch 2 is a switch for selecting whether or not toperform a vehicle stop keeping control (also referred to as SSA:Stand-Still-Assist). The vehicle stop keeping control is a control forgenerating a braking force capable of maintaining the vehicle stoppedstate even when the driver decreases the operation amount of the brakepedal BP from a state in which the vehicle is being stopped (vehiclestopped state) with the operation of the brake pedal BP by the driver.That is, the vehicle stop keeping control is a control for generating abraking force that is capable of maintaining the vehicle stopped stateeven when the brake operation is decreased. In the first embodiment, asan example, a description will be given of a control in which thevehicle stop maintaining control is executed during transition from astate in which the vehicle is stopped by the operation of the brakepedal BP by the driver to a state in which the braking force isgenerated such that the vehicle stop state may be maintained even whenthe brake pedal BP is released by the driver.

In other words, the vehicle stop keeping control is provided forgenerating a braking force capable of maintaining a vehicle stoppedstate as a control performed automatically on the vehicle side,irrespective of manual operation of the brake pedal BP by the driver.Note that “the brake pedal BP is released by the driver” is synonymouswith the degree of opening of the brake pedal BP is brought to 0°. Also,an information signal including the selection result of the vehicle stopkeeping control (in the description below, also referred to as “controlselection signal”) is outputted from the mode selection switch 2 to theidle stop control unit 10.

The vehicle speed calculating unit 4 receives an input of wheel speedsignals from a wheel speed sensor (not shown) including a rotationalspeed of a wheel of the vehicle. Further, the vehicle speed calculatingunit 4 uses the rotational speed included in the wheel speed signal tocalculate a running speed of the vehicle (in the description below, alsoreferred to as “vehicle speed”). Additionally, the vehicle speedcalculating unit 4 outputs to the idle stop control unit 10 informationsignals including the calculated vehicle speed (in the descriptionbelow, also referred to as “vehicle speed signal”). Note that thevehicle speed calculating unit 4, for example, may be configured toinclude a known VDC (Vehicle Dynamics Control) system. The wheel speedsensor is mounted on a vehicle. Further, the wheel speed sensorgenerates a predetermined number of vehicle speed pulses with respect toa vehicle mounted wheel per revolution of the wheel.

The brake sensor BPS is a sensor for detecting the operation amount ofthe brake pedal BP by the driver (depression amount). The brake pedal BPis a pedal that is subject to be depressed by the driver depending onlyon the braking force demand. The brake sensor BPS outputs to the idlestop control unit 10 an information signal including the operationamount of the brake pedal BP by the driver. Incidentally, the brakesensor BPS is formed, for example, by using a pedal stroke sensor.Further, the configuration of the brake sensor BPS is not limited to thestructure formed by using the pedal stroke sensor. For example, it maybe configured to detect a pressure of a master cylinder MS caused bydepression operation of the driver (master cylinder pressure). That is,the brake sensor BPS is a sensor that detects the operation amount ofthe brake pedal BP by the driver (the brake operation).

The hydraulic pressure sensor 6 detects a hydraulic pressure of thebrake fluid supplied from the master cylinder MS to a hydraulic systemof the brake fluid (e.g., dual systems including primary system andsecondary system). The hydraulic pressure sensor 6 (in the descriptionbelow, also referred to as “hydraulic signal”) outputs to the idle stopcontrol unit 10 information signal including the detected hydraulicpressure. The notification unit 20 is formed, for example, by using adisplay device (indicator) arranged in a combination meter or instrumentcluster. In addition, the combination meter is installed in aninstrument panel of the driver's seat. In accordance with theinformation signal input from the idle stop control unit 10, theinformation notification unit 20 selectively causes a display devicedisposed in the combination meter to present the support informationshown in FIG. 2 or to turn off the presented support information.

In a state where the vehicle stop keeping control is activated, thesupport information represents information necessary to establish thepermission condition for carrying out the automatic stop of the engine(which is synonymous with idle stop, idle reduction, and idling stop).That is, the support information is information for establishingpermission condition for automatic engine stop. Note that the “statewhere the vehicle stop keeping control is activated” represents a statein which, regardless of the operation of the brake pedal BP by thedriver, a braking force that can maintain the stopped state of thevehicle is being generated by a control executed automatically by thevehicle.

The permission condition is a condition that has been set in advance. Inthe first embodiment, as an example, a description will be given in acase where the permission condition is defined as the condition in whichthe hydraulic pressure of the brake corresponding to the operationamount of the brake pedal BP reaches a predetermined permissionhydraulic pressure or more. Thus, in a state in which the brakehydraulic pressure corresponding to the operation amount of the brakepedal BP is less than the permission hydraulic pressure, the supportinformation illustrated in FIG. 2 is presented to prompt the driver toincrease the operation amount of the brake pedal BP in order to allowthe brake hydraulic pressure to reach the permission hydraulic pressureor more. Incidentally, the permission hydraulic pressure is set, forexample, to a pressure higher than a brake hydraulic pressure that isable to maintain the stopped state of the vehicle on road surface ofnormal state, for example, on a snow-free flat road surface.

The display that prompts the driver to increase the operation amount ofthe brake pedal BP is, specifically, written information expressing“Please further depress the brake” or a display of icons representingthe graphical relationship between the brake pedal BP and a driver'sfoot. Further, the permission condition may include conditions, forexample, that steering angle of a steering wheel is within a thresholdsteering angle set in advance, the turning direction indicator is off,and/or shift position is at the drive range (“D” range, etc.). That is,the notification unit 20 is configured to notify an occupant of thevehicle of the support information for establishing the permissioncondition. Note that the notification unit 20 may display informationindicating that the vehicle stop keeping control is in operation (e.g.,written information such as “SSA in operation”).

Further, the idle stop control unit 10 includes a vehicle stop keepingcontrol unit 12, an automatic stop control unit 14, an intentiondetermination unit 16, and a notification information control unit 18.The vehicle stop keeping control unit 12 refers to a control selectionsignal received from the mode selection switch 2. Then, when the controlselection signal includes the selection result of performing the vehiclestop keeping control, reference will be made to the vehicle speed signalinput from the vehicle speed calculating unit 4 and the informationsignal input from the brake sensor BPS. Furthermore, the vehicle stopkeeping control unit 12 determines whether or not to operate the vehiclestop keeping control in response to the vehicle speed included in thevehicle speed signal and the operation amount of the brake pedal BPincluded in the information signal received from the brake sensor BPS.

Specifically, when conditions A1 and A2 below are satisfied, adetermination will be made to operate the vehicle stop keeping control.Conditions A1: Vehicle speed is zero (i.e., synonymous with 0 km/h, thesame shall apply below). That is, the vehicle is stopped. Conditions A2:Operation amount of the brake pedal BP is a predetermined amount or more(e.g., zero or the amount to overcome creep torque, also the sameapplies in the following description). That is, the brake pedal BP isoperated. When the vehicle stop keeping control unit 12 determines toexecute the vehicle stop keeping control, a command value for generatinga braking force capable of maintaining the vehicle stop state of thevehicle (in the following description, also referred to as “vehicle stopkeeping command value”) is outputted to the master cylinder MS.

Furthermore, when it has determined to execute the vehicle stop keepingcontrol, the vehicle stop keeping control unit 12 outputs an informationsignal to the automatic stop control unit 14. The information signal(which may also be referred to as “vehicle stop keeping decision signal”in the following description) includes the determination resultindicating to operate the vehicle stop keeping control. Additionally,when it has determined to execute the vehicle stop keeping control, thestop keeping control unit 12 supplies the vehicle stop keeping decisionsignal to the intention determination unit 16 and the notificationinformation control unit 18. Upon receiving an input of vehicle stopkeeping determination signal from the vehicle stop keeping control unit12, the automatic stop control unit 14 determines whether or not thepermission condition is satisfied. If it is determined that thepermission condition is satisfied, a command to stop the running engineENG (may be referred to as “engine stop command” in the descriptionbelow), is outputted to the engine controller EC and the notificationinformation control unit 18. Thus, when the permission condition issatisfied in a state where the braking force capable of maintaining thevehicle stop state is being generated, the automatic stop control unit14 causes the running engine ENG to stop automatically (i.e., causesidle stop, idle reduction, or idling stop).

The intention determination unit 16 determines whether the driverintends to request an automatic stop of the engine ENG in the drivingstate. Thus, the intention determination unit 16 determines whether ornot the driver wishes to automatically stop the engine ENG.Specifically, when receiving an input of vehicle stop keepingdetermination signal from the vehicle stop keeping control unit 12,reference is made to the information signal input from the brake sensorBPS. Then, when a state is confirmed in which the operation amount ofthe brake pedal BP included in the information signal input from thebrake sensor BPS is not changed, or when the operation of the brakepedal BP is released to be zero, it is determined that the driver doesnot wish to stop the engine ENG automatically.

In other words, the intention determination unit 16 in the firstembodiment determines that the driver does not want to automaticallystop the engine ENG when the driver releases the operation of the brakepedal BP while the vehicle stop keeping control is in operation. When itdetermines that the driver does not wish to automatically stop theengine ENG, the driver intention determination unit 16 outputs ano-necessity determination signal to the notification informationcontrol unit 18. The non-necessity determination signal represents aninformation signal including the determination result that the driverdoes not wish to automatically stop the engine ENG.

When it receives an input of the vehicle stop keeping determinationsignal from the vehicle stop keeping control unit 12, the notificationinformation control unit 18 determines whether an input of the enginestop command is being received from the automatic stop control unit 14.That is, when the vehicle stop keeping control is in progress, thenotification information control unit 18 determines whether thepermission condition is satisfied. In a state where input of the vehiclestop keeping determination signal is received from the vehicle stopkeeping control unit 12 but input of the engine stop command is notreceived from the automatic stop control unit 14, a determination willbe made that the permission condition is not satisfied when the vehiclestop keeping control is in progress. Furthermore, an information signal(in the description below, also referred to as “information light-upsignal”) including a command for lighting the support information on thedisplay device is outputted to the information notification unit 20.

Further, after it outputs the support information light-up signal to theinformation notification unit 20, the notification information controlunit 18 determines whether the intention determination unit 16 receivesthe input of the no-necessity determination signal. When theno-necessity determination signal is received from the intentiondetermination unit 16, the information signal (may also be referred toas “information off signal” in the description below) including acommand to turn off the support information is outputted to theinformation notification unit 20. In the first embodiment, an example isgiven in which the configuration of the notification information controlunit 18 is such that, after a notification continuation time uponreceipt of the input of the no-necessity determination signal haselapsed, the information off signal is outputted to the informationnotification unit 20. The notification continuation time is a presettime. Further, the notification continuation time is set, for example,according to a vehicle class (corresponding to a body size and/or anexhaust amount of engine ENG, rating of the vehicle, etc.) and,depending on the position (viewing position) of the display deviceprovided in the information notification unit 20. In the firstembodiment, as an example, the notification continuation time is set to2 sec.

In the first embodiment, an example is given for a case where theconfiguration of the notification information control unit 18 is made asdescribed below. Specifically, the notification information control unit18 of the first embodiment is configured such that, until a notificationreserved time has elapsed from the start of the notification of thesupport information, even when determined that the driver does not wishto automatically stop the engine ENG, stopping of the notification ofthe support information is delayed. The notification reserved time is apreset time. Further, the notification reserved time is set, similar tothe notification continuation time, according to, for example, thevehicle class, the position (viewing position) of the display deviceprovided in the information notification unit 20. In the firstembodiment, as an example, the notification reserved time is set to 2sec.

Thus, the notification information control unit 18 causes theinformation notification unit 20 to notify the support information whenthe permission condition is not satisfied in a state in which thevehicle stop keeping control is operating or in operation. Further, in astate in which the support information is notified from the informationnotification unit 20, the notification of the support information isstopped when determined that the driver does not wish to stop the engineautomatically. Furthermore, the notification information control unit 18is configured such that, in a state in which the support information isnotified, a time interval is set as a predetermined notificationcontinuation time between a determination that the driver does not wishto stop the engine ENG automatically and actually stopping thenotification of the support information.

The master cylinder MS is a device for supplying the brake oil (brakefluid) to the wheel cylinder WS. In response to receiving the stopkeeping command value from the idle stop control unit 10, the mastercylinder MS moves a piston inside the master cylinder MS by operating abraking motor (not shown) accommodated in the master cylinder MS. Thus,in the master cylinder MS, a hydraulic pressure is generatedcorresponding to the vehicle stop keeping command value. Then, thehydraulic pressure of the brake fluid in accordance with the stopkeeping command value is supplied to the wheel cylinder WS.

The wheel cylinder WS is operable to generate a pressing force forpressing a brake pad constituting the disk brake (not shown) to a diskrotor (not shown). The disk rotor rotates integrally with the wheel W,and frictional resistance is generated by contacting the brake pad. Thatis, the master cylinder MS and the wheel cylinder WS are mounted on thewheel to form a friction brake to generate a frictional braking force onthe wheels. The engine controller EC is operable to stop the engine ENGin operation in response to an engine stop command received from theidle stop control unit 10. The engine ENG forms a driving force ortorque source of the vehicle. As described above, the idle stop controlunit 10 uses the various types of information signals received tocontrol the master cylinder MS, the engine controller EC, and theinformation notification unit 20 provided in the vehicle.

Processing Performed by Idle Stop Control Unit 10

With reference to FIGS. 1 and 2, and using FIG. 3, an example ofprocessing performed by the idle stop control unit 10 is given. In thedescription below, the processing of the idle stop control unit 10 maybe referred to as “the vehicle control process”. Further, the processillustrated in FIG. 3 specifies the processing in a case in which themode selection switch 2 is selected to perform the vehicle stop keepingcontrol. As represented in FIG. 3, upon starting the vehicle controlprocess (START), processing of step S100 is executed. In step S100, thevehicle speed calculating device 4 calculates the vehicle speed(expressed in FIG. 3 as “Calculate Vehicle Speed”). After calculatingthe vehicle speed in step S100, the vehicle control process proceeds tostep S102.

In step S102, it is determined whether or not the vehicle is stopped(expressed in FIG. 3 as “Vehicle Stopped?”) by confirming that thevehicle speed calculated in step S100 is zero. When determined in stepS102 that the vehicle is stopped (expressed in FIG. 3 as “Yes”), thevehicle control process proceeds to step S104. On the other hand, instep S102, when determined that the vehicle is not stopped (expressed inFIG. 3 as “No”), the vehicle control process proceeds to step S100. Instep S104, by the automatic stop control unit 14, processing isperformed for determining whether or not a permission condition issatisfied (expressed in FIG. 3 as “Permission Condition Satisfied?”). Instep S104, when the permission condition is determined to be satisfied(represented in FIG. 3 as “Yes”), the vehicle control process proceedsto step S114. On the other hand, in step S104, when determined that thepermission condition is not satisfied (expressed in FIG. 3 as “No”), thevehicle control process proceeds to step S106.

In step S106, processing is performed by the vehicle stop keepingcontrol unit 12 for determining whether or not the vehicle stop keepingcommand value is outputted to the master cylinder MS. That is,processing is carried out in step S106 for determining whether or notthe vehicle stop keeping control is activated and in operation(expressed in FIG. 3 as “SSA in Operation?”). In step S106, when thevehicle stop keeping control is determined to be in operation (expressedin FIG. 3 as “Yes”), the vehicle control process proceeds to step S108.On the other hand, in step S106, when determined that the vehicle stopkeeping control is not in operation (expressed in FIG. 3 as “No”), thevehicle control process proceeds to step S116.

In step S108, the information turn on or light-up signal is output fromthe notification information control unit 18 to the informationnotification unit 20. Thus, in step S108, the support information is liton the display device (represented in FIG. 3 as “Turn on SupportInformation”). In step S108, when the support information is lit on thedisplay device, the vehicle control process proceeds to step S110. Instep S110, processing is performed by the intention determination unit16 to determine whether or not the operation amount of the brake pedalBP is zero (expressed in FIG. 3 as “Brake OFF?”). When determined instep S110 that the operation amount of the brake pedal BP is zero(expressed in FIG. 3 as “Yes”), the vehicle control process proceeds tostep S112. On the other hand, in step S110, when determined that theoperation amount of the brake pedal BP is greater than zero (representedin FIG. 3 as “No”), the vehicle control process proceeds to step S116.

In step S112, the notification information control unit 18 determineswhether or not the notification continuation time (2 sec) has elapsedafter the operation amount of the brake pedal BP is determined to bezero in step S110 (expressed in FIG. 3 as “Notification ContinuationTime Elapsed?”). In step S112, when it is determined that thenotification continuation time has elapsed since the operation amount ofthe brake pedal BP being determined to be zero in step S110 (expressedin FIG. 3 as “Yes”), the vehicle control process proceeds to step S114.On the other hand, in step S112, when it is determined that thenotification continuation time has not elapsed since the operationamount of the brake pedal BP is determined to be zero (expressed in FIG.3 as “No”) in step S110, the vehicle control process proceeds to stepS104.

In step S114, the information turn off signal is output from thenotification information control unit 18 to the information notificationunit 20. Thus, in step S114, the support information that is lit on thedisplay device will be turned off (expressed in FIG. 3 as “Turn OffSupport Info.”). In step S114, upon turning off the support informationthat has been lit on the display device, the vehicle control processends (END). In step S116, similar to step S110, the intentiondetermination unit 16 performs processing for determining whether or notthe operation amount of the brake pedal BP is zero (expressed in FIG. 3as “Brake OFF?”). In step S116, when the operation amount of the brakepedal BP is determined to be zero (expressed in FIG. 3 as “Yes”), thevehicle control process proceeds to step S114. On the other hand, instep S116, when determined that the operation amount of the brake pedalBP is greater than zero (expressed in FIG. 3 as “No”), the vehiclecontrol process proceeds to step S104.

Operation

With reference to FIGS. 1 to 3, and using FIG. 4, an example will beexplained of operations performed using the vehicle informationproviding device 1 of the first embodiment. Incidentally, in FIG. 4, atime chart of operations is shown, which are performed by theconfiguration according to the vehicle information providing device 1 inthe first embodiment. Also, in the time chart shown in FIG. 4, a case isdepicted in which the mode selection switch 2 is selected to put thevehicle stop keeping control in operation. The time chart shown in FIG.4 starts from a state in which the driver operates or presses down abrake pedal BP (i.e., Brake ON) during travel of the vehicle (i.e.,vehicle speed>0). Incidentally, in the profile represented by “Brake” inFIG. 4, a situation in which the operation amount of the brake pedal BPis zero is expressed as “OFF” while another situation in which theoperation amount of the brake pedal BP exceeds zero is expressed as“ON”.

At the starting time of the time chart shown in FIG. 4, since a brakefluid or hydraulic pressure corresponding to the operation amount of thebrake pedal BP of the driver is generated, the vehicle speed decreases.Further, at the starting time of the time chart shown in FIG. 4, thevehicle stop keeping control is not in operation (SSA OFF). Thus, thesupport information is turned off (brake press-down prompting indicatoris turned off). Furthermore, at the starting time of the time chartshown in FIG. 4, the engine is being driven. Thus, the idle stop is notin operation or activated (IS inoperative). Note that, on the profilerepresented by “SSA” in FIG. 4, a state in which the vehicle stopkeeping control is in operation is expressed as “ON” while a state inwhich the vehicle stop keeping control is not in operation is expressedas “OFF”. Similarly, in the profile graph represented by “BrakePress-down Prompting Indicator” in FIG. 4, a state in which the supportinformation is lit is expressed as “Turn ON” while a state in which thesupport information is extinguished is expressed as “Turn OFF”.Furthermore, in the profile represented by “IS” in FIG. 4, a state inwhich the idle stop is not in operation is expressed as “ISinoperative”.

At the time (time t1) in FIG. 4 when the vehicle speed reaches zero,i.e., when the vehicle comes to stop, it is determined whether or not acondition is satisfied in which the operation amount of the brake pedalBP is greater than zero. Then, at the time at which the operation amountof the brake pedal BP is determined to be greater than zero (time t2),the vehicle stop keeping control (SSA ON) is operated. Incidentally, thebrake hydraulic pressure at time t1 represents, for example, a brakehydraulic pressure that is great enough to maintain a vehicle stop stateagainst a creep torque generated in the vehicle with the engine ENGbeing driven.

Further, the support information is turned on (i.e., brake press-downprompting indicator is turned on) at a point in time (time t3) when apredetermined post-vehicle-stop turn off time has elapsed. In the firstembodiment, as an example, the post-vehicle-stop turn off time is setbetween 2 sec and 3 sec. After the time t3, the operation amount of thebrake pedal BP by the driver starts decreasing (time t4). When theoperation amount of the brake pedal BP reaches zero (time t5), the brakehydraulic pressure that started decreasing from time t4 reaches zero atthe time t5 (expressed “0” in FIG. 4). Note that the brake hydraulicpressure being zero has the same meaning as the brake hydraulic pressureattaining 0 kg/cm². That is, at time point t5, the operation amount ofthe brake pedal as well as the brake hydraulic pressure will reach zero(Brake OFF, Brake hydraulic pressure zero).

Further, on the time chart in FIG. 4, the permission condition is notsatisfied up to the time point t4 because the brake hydraulic pressureis lower than the permission hydraulic pressure. Thus, the automaticstop of the engine ENG is not performed. In other words, from the starton the time chart shown in FIG. 4 to the time point t4, the engine isbeing driven and thus the idle stop is not performed (IS inoperative).Then, at a time (time t6) when a notification continuation time haselapsed from the time t5, the support information that was lit at thetime t3 is extinguished (brake press-down indicator is turned off).Although not shown, in the operation performed using the vehicleinformation providing device 1 in the first embodiment, the supportinformation will be turned off when an accelerator pedal provided in thevehicle is operated in a state in which the support information isturned on.

As described above, with the vehicle information providing device 1 ofthe first embodiment, a determination is made as to whether or not thedriver wishes an automatic stop of the engine ENG to be performed whenthe vehicle stop keeping control is in operation. Subsequently, when itis determined that the driver does not wish to perform the automaticstop of the engine ENG, notification of the support information will bestopped. Accordingly, while the support information is being notifiedwhen the stop keeping control is in operation, it is possible to stopthe notification of the support information when the driver does notwish to perform the operation of the idle stop.

As described above, according to the information providing method for avehicle using the information providing device 1 of the firstembodiment, the engine ENG is automatically stopped when a permissioncondition is satisfied in a state in which the vehicle is stopped by abrake operation of the driver (operation of brake pedal BP). Further, ina state in which the vehicle is stopped by the brake operation of thedriver (operation of brake pedal BP), support information will beprovided to the driver if the permission condition is not established.Furthermore, when the support information is being notified and thevehicle stop keeping control is in operation, the notification of thesupport information will be stopped upon if it is determined that thedriver does not wish to stop the engine automatically.

In other words, despite the notification to the driver that the engineENG will be stopped automatically if the brake operation is slightlyincreased, it is determined that the driver does not wish for the engineENG to be stopped automatically judging from a state in which the driverdoes not increase depression of the brake pedal BP. Note that the statein which the driver does not increase depression of the brake pedal BPincludes a state in which the driver maintains the operation amount ofthe brake pedal BP as well as a state in which the driver decreases theoperation amount of the brake pedal BP. Incidentally, the firstembodiment described above is an example of the present invention. Thepresent invention is not limited to the first embodiment describedabove. Even in configurations other than the present embodiment, variousmodifications in design and the like are available unless they do notdepart from the technical idea of the present invention.

(Effects of the First Embodiment)

According to the vehicle information providing method using the vehicleinformation providing device 1 in the first embodiment, it is possibleto achieve the effects described below.

-   (1) When a permission condition is unsatisfied in a state in which    the vehicle is stopped by a brake operation of the driver    (depression of brake pedal BP), the support information is notified    to the driver. Further, in a state in which the support information    is being notified and the vehicle stop keeping control is in    operation, the notification of the support information is stopped    when it is determined that the driver does not wish to stop the    engine ENG automatically. Thus, in a state in which the support    information is being notified and the vehicle stop keeping control    is in operation, the notification of the support information is    stopped when it is determined that the driver does not wish to stop    the engine ENG automatically. As a result, it is possible to stop    notification of the support information in a situation in which the    driver does not wish to operate the idle stop. Therefore, in the    situation in which the driver does not wish to operate the idle    stop, it is possible to prevent unnecessary support information from    being continuously displayed.-   (2) It is determined that the driver does not wish to stop the    engine ENG automatically when the operation of the brake pedal BP is    released while the vehicle stop keeping control is in operation.    Thus, by detecting a vehicle speed and the operation amount of the    brake pedal BP, it is possible to determine whether the driver    wishes to stop the engine ENG automatically. As a result, using an    existing configuration in the vehicle, it is possible to determine    whether or not the driver wishes to stop the engine ENG    automatically.-   (3) In a state in which the support information is being notified, a    time interval is set as a predetermined notification continuation    time (e.g., 2 sec) that extends from the determination that the    driver does not wish to stop the engine ENG automatically until the    notification of the support information is stopped. Therefore, even    when it is determined that the driver does not wish to automatically    stop the engine ENG, it is possible to continue the notification of    the support information for at least the duration of the    notification continuation time. As a result, even when the driver    does not wish to automatically stop the engine ENG, it is possible    for the driver to increase the possibility of recognition (visually)    of the support information.-   (4) Stopping of notification of the support information is delayed    until a notification reserved time elapses from start of    notification of the support information, even when it is determined    that the driver does not wish to step the engine ENG automatically.    Therefore, even when it is determined that the driver does not wish    to operate an automatic stop of the engine ENG, it is possible to    notify the support information for at least the duration of the    notification reserved time. As a result, even when the driver does    not wish to automatically stop the engine ENG, it is possible to    increase the possibility of recognition (visually) by the driver. In    addition, with the vehicle information providing device 1 of the    first embodiment, it is possible to achieve the effects below.-   (5) In a state in which the vehicle is stopped due to operation of    brake pedal BP by the driver, the automatic stop control unit 14    stops the engine ENG automatically when it is determined that the    permission condition is satisfied. Further, the vehicle stop keeping    control unit 12 executes a vehicle stop keeping control that causes    a braking force to be generated that can maintain the vehicle stop    state even when the driver decreases the brake operation from a    state in which the vehicle is stopped by the operation of the brake    pedal BP by the driver. In addition, in a state in which the vehicle    is stopped by the operation of the brake pedal BP by the driver, the    notification information control unit 18 notifies the support    information from the information notification unit 20 when the    permission condition is not satisfied. Furthermore, in a state in    which the support information is being notified and the vehicle stop    keeping control is in operation, the notification of the support    information is stopped when the intention determination unit 16    determines that the driver does not wish to stop the engine ENG    automatically.

Thus, when the support information is being notified and the vehiclestop keeping control is in operation, the notification of the supportinformation is stopped upon determining that the driver does not wish tostop the engine ENG automatically. As a result, in a situation in whichthe driver does not wish to operate the idle stop, it is possible tostop the notification of the support information. Therefore, insituations in which the driver does not wish to operate the idle stop,it is possible to prevent the unnecessary support information from beingcontinuously displayed.

Modifications of the First Embodiment

(1) In the first embodiment, when the operation of the brake pedal BP isreleased with the vehicle stop keeping control in operation, it isdetermined that the driver does not wish to stop the engine ENGautomatically. However, the configuration by which to determine whetheror not the driver wishes to stop the engine ENG automatically is notlimited to this example. More specifically, it is acceptable to adopt aconfiguration in which it is determined that the driver does not wish tostop the engine ENG automatically when the operation amount of the brakepedal BP decreases while the vehicle stop keeping control is inoperation. In this case, on the time chart shown in FIG. 4, it isdetermined that the driver does not wish to stop the engine ENGautomatically at the time t4. With this configuration, as compared withthe configuration of the first embodiment, it is possible to shorten thetime required to determine that the driver does not want to stop theengine ENG automatically.

(2) In the first embodiment, when the operation of the brake pedal BP isreleased with the vehicle stop keeping control being in operation, it isdetermined that the driver does not wish to stop the engine ENGautomatically. However, the configuration by which to determine whetheror not the driver wants to stop the engine ENG automatically is notlimited to this example. More specifically, it is acceptable to adopt aconfiguration in which it is determined that the driver does not wish tostop the engine ENG automatically when the brake hydraulic pressure isless than a predetermined determination hydraulic pressure with thevehicle stop keeping control is in place. The determination hydraulicpressure is, for example, a hydraulic pressure which is set to less thanthe permission hydraulic pressure. The determination hydraulic pressuremay be set to any value according to the vehicle class of the vehicleand the like. With this configuration, it is possible to determine thatthe driver does not wish to stop the engine ENG automatically even whenthe brake hydraulic pressure varies below the determination hydraulicpressure in response to the operation amount of the brake pedal BP bythe driver. Thus, as compared with the configuration of the firstembodiment, it is possible to shorten the time required to determinethat the driver does not want to stop the engine ENG automatically.

(3) In the first embodiment, when the operation of the brake pedal BP isreleased with the vehicle stop keeping control in operation, it isdetermined that the driver does not wish to stop the engine ENGautomatically. However, the configuration by which to determine whetheror not the driver wishes to stop the engine ENG automatically is notlimited to this example. More specifically, it is acceptable to adopt aconfiguration in which it is determined that the driver does not wish tostop the engine ENG automatically when the time the brake hydraulicpressure is less than a predetermined determination hydraulic pressurecontinues for a determination time period with the vehicle stop keepingcontrol is in operation, it may be. In this configuration, it ispossible to determine definitively that the driver does not wish to stopthe engine ENG automatically even when the brake hydraulic pressurevaries according to the operation amount of the brake pedal BP by thedriver below the determination hydraulic pressure until thedetermination time period will expire. In this configuration, ascompared with the configuration of the first embodiment, it is possibleto improve the reliability to determine that the driver does not want tostop the engine ENG automatically.

(4) In the first embodiment, in a state in which the support informationis notified, a time interval is set as a predetermined fixed value ofnotification continuation time between determination that the driverdoes not wish to stop the engine ENG automatically and stopping of thenotification of the support information. However, the notificationcontinuation time is not limited to this example. More specifically, thenotification continuation time may be changed using the notificationcontinuation time calculation map represented in FIG. 5. Specifically,the notification continuation time may be shorter as the time elapsed islonger from starting the determination of whether or not the driverwishes to stop the engine ENG automatically until it is determined thatthe driver does not wish to stop the engine ENG automatically. Note thatin FIG. 5, on the horizontal axis, a time elapsed from the start ofdetermination of whether or not the driver wishes to automatically stopthe engine ENG until determination that the driver does not want toautomatically stop the engine ENG is expressed as “elapsed time fordetermination”. Also, the elapsed time for determination is the timeduring which lighting of the support information is continued. In thiscase, it is possible to correlate the determination as to whether or notthe driver wishes to stop the engine ENG automatically and the length oftime during which the support information is continuously notified.

(5) In the first embodiment, although the support information is anindication or display for prompting the driver to increase the operationamount of the brake pedal BP as shown in FIG. 2, the support informationis not limited to this example. That is, the support information may be,for example, a sound (voice, alarm, etc.) to encourage the driver toincrease the operation amount of the brake pedal BP.

(6) In the first embodiment, in a state in which the support informationis notified, the time interval from the determination that driver doesnot wish to stop the engine ENG automatically until stopping thenotification of the support information is set to the notificationcontinuation time. However, the present invention is not limited to thisexample. That is, notification of the support information may be stoppedat the point in time when it is determined that the driver does not wishto stop the engine ENG automatically (for example, at the time t5represented in FIG. 4).

(7) In the first embodiment, the brake operation by the driver isspecified as the operation of the brake pedal BP by the driver. However,the operation by the driver is not limited thereto. That is, when theconfiguration of the vehicle is such that, for example, a brake lever isprovided for instructing the braking force of the vehicle bymanipulating by hand, the operation of the brake lever by the driver maybe interpreted as the brake operation by the driver.

The invention claimed is:
 1. An information providing method for avehicle, the information providing method comprising: stopping an engineof the vehicle automatically when a predetermined permission conditionis satisfied in a state in which the vehicle is stopped by a brakeoperation of a brake of the vehicle executed by a driver: notifying thedriver of support information for satisfying the permission conditionwhen the permission condition is not satisfied in the state in which thevehicle is stopped by the brake operation: starting a vehicle stopkeeping control that generates a braking force capable of maintaining avehicle stopped state even when the brake operation decreases; stoppingthe notification of the support information when it has been determinedthat the driver does not wish to automatically stop the engine while ina state in which the support information is being notified and thevehicle stop keeping control is in operation, the determination that thedriver does not wish to stop the engine automatically being based on thedriver not increasing a brake operation amount of the brake afterexecuting the brake operation: and setting a time interval from thedetermination that the driver does not wish to stop the engineautomatically until the notification of the support information isstopped as a notification continuation time that is set to be shorter asan elapsed time becomes longer from starting to determine whether thedriver wishes to stop the engine automatically until the determinationthat the driver does not wish to stop the engine automatically is made.2. The information providing method according to claim 1, wherein thedetermination that the driver does not wish to stop the engineautomatically is made when a brake hydraulic pressure according to thebrake operation amount is less than a predetermined determinationhydraulic pressure.
 3. The information providing method according toclaim 2, wherein the determination that the driver does not wish to stopthe engine automatically is made when an amount of time over which thebrake hydraulic pressure is less than the predetermined determinationhydraulic pressure continues for a determination time period set inadvance.
 4. The information providing method according to claim 1,wherein the determination that the driver does not wish to stop theengine automatically is made when the brake operation is released.